Technical Field
The invention relates to an optical fiber temperature distribution measurement system and an optical fiber temperature distribution measurement method for detecting a roller abnormality of a belt conveyor.
Related Art
A system configured to measure temperatures near a belt conveyor by using an optical fiber temperature distribution measurement device (DTS: Distributed Temperature Sensor) and to detect a fire of the belt conveyor has been known.
The configuration of measuring temperatures near the belt conveyor and detecting a fire of the belt conveyor is very beneficial because it enables an initial fire extinguishing. However, the information obtained by the temperatures near the belt conveyor is not limited to the fire occurrence.
For example, if a roller of the belt conveyor cannot smoothly rotate due to failure, aging degradation or the like, a temperature of a rotating part increases by friction. For this reason, it is also possible to detect a roller abnormality by measuring the temperatures near the belt conveyor. Since the roller abnormality may increase a load of the belt conveyor and the increase in temperature due to the friction may cause a firing, it is preferably detect the roller abnormality at an early stage.
[Patent Document 1] Japanese Patent Application Publication No. 2014-83297A
However, the temperature increased due to the roller abnormality is very lower, as compared to the temperature upon the fire, and is also local. For this reason, the temperature may be hidden by noises or may not be sufficiently expressed in measured values due to a limit of a spatial resolution of the optical fiber temperature distribution measurement device.
A configuration of circulating an optical fiber in a coil shape in the vicinity of the roller so as to secure a length of the optical fiber disposed in the vicinity of the roller or detecting a slight change in temperature by bringing the optical fiber into close contact with a metal part configured to support the roller is considered. However, the above configuration should be provided for each roller. Therefore, a troublesome work for laying down the optical fiber is required, which increases the cost.